Maltose selective benzoylation

Selective de-esterification of octa-0-benzoyl-/3-maltose has been... 

The C-4 position of maltose can be modified in a similar way. Maltose, being a reducing sugar, usually has to have C-1 protected. C-1 is often protected by forming the 1,2-0-isopropylidene derivative. It has been obtained in a 33% yield and represented one of four isopropylidene compounds that were formed [111]. These compounds had to be separated on a silica-gel column. The 1,2-isopropylidene maltose is then reacted with 1,1-dimethoxy benzaldehyde to give the 4, 5 -benzili-dene derivative (reaction 4.116). The other free hydroxyl groups are protected by benzoylation, and the C-4 -0 bond is selectively cleaved to produce the free C-4 ... 

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